Citri Reticulatae Pericarpium extract suppresses adipogenesis in 3T3-L1 preadipocytes

This study examined how Citrus herbal medicines - Citri Reticulatae Pericarpium (CRP), Citri Reticulatae Viride Pericarpium (CRVP), Aurantii Immaturus Fructus (AIF) and Aurantii Fructus (AF) - affect the differentiation of 3T3-L1 adipocytes. Eight days after induction for differentiation with 3-isobutyl-1-thylxanthine, dexamethasone and insulin (MDI) medium and simultaneously with the tested CRP, intracellular triacylglycerol accumulations of 3T3-L1 cells were significantly (P < 0.05) reduced compared with those for CRVP, AIF and AF and those of the vehicle control. This suppression affect was dose-dependent, and decreases in triacylglycerol production of 12.6, 18.7, 34.05 and 49.6% were observed for CRP at concentrations of 50, 100, 150 and 200 mu g mL(-1) respectively. Additionally, the expression of key transcription factors for the 3T3-L1 adipogenesis gene, including PPAR-gamma, CIEBP-alpha and SREBP-1, was markedly reduced by CRP treatment. These results suggest that dietary CRP suppresses 3T3-L1 differentiation by down-regulation of adipogenic transcription factors. Experimental data may prove useful in further medical examination of the use of CRP for body weight control. (C) 2007 Society of Chemical Industry.